1. Technical Field
The present invention relates to a method for manufacturing a semiconductor device having a reverse staggered thin film transistor including a crystalline semiconductor film.
2. Background Art
In recent years, a flat panel display (FPD) as typified by a liquid crystal display (LCD) or an EL (Electro Luminescence) display has attracted attention as a display device which can take the place of the conventional CRT. Particularly, the development of a large screen liquid crystal television mounted with an active matrix large liquid crystal panel is an important issue which should be focused by a liquid crystal panel manufacturer. A large screen EL television has been developed in recent years following the development of a liquid crystal television.
In the conventional liquid crystal display device or EL display device (hereinafter, light-emitting display device), a thin film transistor (hereinafter, TFT) using an amorphous semiconductor film (amorphous silicon) is used as a semiconductor element for driving each pixel.
With respect to the conventional liquid crystal television, there are defects such as the limits of viewing angle characteristics and the blurring of an image due to the limits of high speed operation caused by a liquid crystal material or the like. However, an OCB (Optically Compensated Bend) mode has been proposed in recent years as a novel display mode for removing the defects (for example, refer to non patent document 1).    [Non Patent Document 1] “Nikkei Micro Device Separate Volume, Flat Panel Display 2002”, Edited by Yasuaki Nagahiro, Nikkei Business Publications, Inc., October 2001, pp. 102-109.